javascript - 如果某些键使用 JavaScript 相同，则从另一个数组构建数组

Question

我有一组数据。数组中的一些键是相同的。我想根据键创建一个新数组并添加其他数据。

这是我的数组

 var myObjOne = [
        {
        "name":"John",
        "id":1,
        "car":"maruti"
       },
       {
        "name":"John",
        "id":2,
        "car":"wolks"
       },
       {
        "name":"John",
        "id":3,
        "car":"bmw"
       },        
      {
        "name":"Peter",       
        "id":4, 
        "car":"alto"                           
      },
      {
        "name":"Peter",       
        "id":5, 
        "car":"swift"                           
      }
    ];

我想将数组转换为以下格式。

var myObj = [
          {
          "name":"John",
          "items": [
              { "id":1, "car":"maruti" },  
              { "id":2, "car":"wolks" },
              { "id":3, "car":"bmw" }            
          ]},
          {
            "name":"Peter",
          "items": [
              { "id":4, "car":"alto" },  
              { "id":5, "car":"swift" },                          
          ]
       }
      ];

我正在开发节点环境。

Answer 1

您可以使用 Array#reduce 创建对象首先将名称与项目映射，然后通过使用 for...of 遍历中间映射来创建最终数组循环:

var source = [{"name":"John","id":1,"car":"maruti"},{"name":"John","id":2,"car":"wolks"},{"name":"John","id":3,"car":"bmw"},{"name":"Peter","id":4,"cars":"alto"},{"name":"Peter","id":5,"cars":"swift"}];

const map = source.reduce((acc, {name, ...obj}) => {
  if (!acc[name]) {
    acc[name] = [];
  }
  
  acc[name].push(obj);
  return acc;
}, {});

const result = [];

for (let[name, items] of Object.entries(map)) {
  result.push({name, items});
}

console.log(result);